Southwest Airlines is having their annually 72 hour sale where they offer flights round trip to certain destinations for as little as $49. Its so cheap, but it comes with some restrictions as well as wanting to fly on a Tuesday, Wednesday, or Saturday.

Southwest flies out of Detroit, Grand Rapids, and Flint and all of them have round trip flights to Chicago at $49, as well as Baltimore and Denver which have different prices, which you can check out from southwest here. But know that there isn't that wide of a variety of places where you can go from a Michigan Airport. So you best option might be flying to Chicago for cheap and trying to find another cheap flight from there since Midway flies to more places.